There is a need particularly in the telecommunications industries for back-up power source to maintain operations when the primary source shuts down. These systems generally comprise a plurality of valve regulated lead acid batteries (VRLA), generally of a two (2) volt size which are typically connected in series in various numbers such as 24 batteries to provide a 48 volt system. Typically, these batteries are supported in battery rack systems of the type shown, for example, in U.S. Pat. No. 6,719,150 issued Apr. 13, 2004 entitled BATTERY RACK AND SYSTEM and owned by the Assignee of the present invention. This prior system is generally effective for the purposes intended. However, there are some installations where the space requirements for the racks are tight and where assembly and mounting of the rack system in these confined areas is difficult and time consuming.